Troglitazone (Rezulin, Resulin, Romozin, Noscal) is an antidiabetic and anti-inflammatory drug, and a member of the drug class of the thiazolidinediones. It was prescribed for patients with diabetes mellitus type 2.[1] It was developed by Daiichi Sankyo Co.(Japan). In the United States, it was introduced and manufactured by Parke-Davis in the late 1990s, but turned out to be associated with an idiosyncratic reaction leading to drug-induced hepatitis. One F.D.A. medical officer evaluating troglitazone, John Gueriguian, did not recommend its approval due to potential high liver toxicity,[2] but a full panel of experts approved it in January 1997.[3] Once the prevalence of adverse liver effects became known, troglitazone was withdrawn from the British market in December 1997, from the United States market in 2000, and from the Japanese market soon afterwards. It didn't get approval in the rest of Europe.

Contents

1Approval history

2Lawsuits

3Mode of action

4References

5External links

Approval history

Parke-Davis/Warner Lambert submitted the diabetes drug Rezulin for U.S. Food and Drug Administration (F.D.A.) review on July 31, 1996. The medical officer assigned to the review, Dr. John L. Gueriguian, cited Rezulin's potential to harm the liver and the heart and he questioned its viability in lowering blood sugar for patients with adult-onset diabetes, recommending against the drug's approval. After complaints from the drugmaker, Gueriguian was removed on November 4, 1996 and his review was purged by the F.D.A.[4][5] Parke-Davis said at the advisory committee that the risk of liver toxicity was comparable to placebo and that additional data of other studies confirmed this.[6] When the company provided these additional data one week after approval, they showed a substantial greater risk for liver toxicity.[7]

The F.D.A. approved the drug on January 29, 1997, and it appeared in pharmacies in late March. At the time Dr. Solomon Sobel, a director at the F.D.A., overseeing diabetes drugs, said in a New York Times interview that adverse effects of troglitazone appeared to be rare and relatively mild.[8]

Glaxo Wellcome P.L.C. received approval from the British Medicines Control Agency (MCA) to market troglitazone, as Romozin, in July 1997.[9] After reports of sudden liver failure in patients receiving the drug, Glaxo removed troglitazone from the market in Britain on December 1, 1997.[4] Glaxo had licensed the drug from Sankyo Company of Japan and had sold it in Britain from October 1, 1997.[10][11]

The F.D.A. and Warner-Lambert responded to the U.K. withdrawal of troglitazone by recommending that patient liver-function be monitored on a monthly basis. On May 17, 1998, a 55-year old patient named Audrey LaRue Jones died of acute liver failure after taking troglitazone. Importantly, she had been monitored closely by physicians at the National Institutes of Health as a participant in the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) diabetes prevention study.[12][13] This called into question the efficacy of the monitoring strategy. The N.I.H. responded on June 4 by dropping troglitazone from the study.[5][14] Dr. David J. Graham, an F.D.A. epidemiologist charged with evaluating the drug, warned on March 26, 1999 of the dangers of using it and concluded that patient monitoring was not effective in protecting against liver failure. He estimated that the drug could be linked to over 430 liver failures and that patients incurred 1,200 times greater risk of liver failure when taking Rezulin.[5][15] Dr. Janet B. McGill, an endocrinologist who had assisted in the Warner–Lambert's early clinical testing of Rezulin, wrote in a March 1, 2000 letter to Sen. Edward M. Kennedy (D-Mass.): "I believe that the company . . . deliberately omitted reports of liver toxicity and misrepresented serious adverse events experienced by patients in their clinical studies."[16]

On March 21, 2000, the F.D.A. withdrew the drug from the market.[17] Dr. Robert I. Misbin, an F.D.A. medical officer, wrote in a July 3, 2000 letter to the House Energy and Commerce Committee of strong evidence that Rezulin could not be used safely, after having been threatened by the FDA with dismissal in March 2000.[4][18] By that time the drug had been linked to 63 liver-failure deaths and had generated sales of more than $2.1 billion for Warner-Lambert.[15] The drug cost $1,400 a year per patient in 1998.[11] Pfizer, which had acquired Warner-Lambert in February 2000, reported the withdrawal of Rezulin cost $136 million.[19]

Lawsuits

In 2009 Pfizer Inc. resolved all but three of 35,000 claims over its withdrawn diabetes drug Rezulin for a total of about $750 million. Pfizer, which acquired rival Wyeth for almost $64 billion, paid about $500 million to settle Rezulin cases consolidated in federal court in New York, according to court filings. The company also paid as much as $250 million to resolve state-court suits. In 2004, it set aside $955 million to end Rezulin cases.[20]

Mode of action

Troglitazone, like the other thiazolidinediones (pioglitazone and rosiglitazone), works by activating peroxisome proliferator-activated receptors (PPARs).

Troglitazone is a ligand to both PPARα and – more strongly – PPARγ. Troglitazone also contains an α-tocopheroyl moiety, potentially giving it vitamin E-like activity in addition to its PPAR activation. It has been shown to reduce inflammation:[21] troglitazone use was associated with a decrease of nuclear factor kappa-B (NF-κB) and a concomitant increase in its inhibitor (IκB). NFκB is an important cellular transcription regulator for the immune response.

^ abFisher, Lawrence (17 January 1998). "Drug Makers at Threshold of a New Therapy; With a Dose of Biotechnology, Big Change Is Ahead in the Treatment of Diabetes". The New York Times. Retrieved 12 December 2012.

^Diabetes Prevention Research Group (April 1999). "Design and methods for a clinical trial in the prevention of type 2 diabetes". Diabetes Care22 (4): 623–634. doi:10.2337/diacare.22.4.623. Retrieved 12 December 2012.

^Diabetes Prevention Program Research Group (7 February 2002). "Reduction in the Incidence of Type 2 Diabetes with Lifestyle Intervention or Metformin". The New England Journal of Medicine346 (6): 393–403. doi:10.1056/NEJMoa012512. PMC 1370926. PMID 11832527. Retrieved 12 December 2012.

Note: Anabolic steroids, including those that are only weakly virilizing (or even anti-virilizing (e.g., oxandrolone)), are included here (since their anabolic effects are nonetheless mediated via activation of the androgen receptor).

Troglitazone (Rezulin, Resulin, Romozin, Noscal) is an antidiabetic and anti-inflammatory drug, and a member of the drug class of the thiazolidinediones. It was prescribed for patients with diabetes mellitus type 2.[1] It was developed by Daiichi Sankyo (Japan). In the United States, it was introduced and manufactured by Parke-Davis in the late 1990s, but turned out to be associated with an idiosyncratic reaction leading to drug-induced hepatitis. The F.D.A. medical officer assigned to evaluate troglitazone, John Gueriguian, did not recommend its approval due to potential high liver toxicity; Parke-Davis complained to the FDA and Gueriguian was subsequently removed from his post.[2] A full panel of experts approved it in January 1997.[3] Once the prevalence of adverse liver effects became known, troglitazone was withdrawn from the British market in December 1997, from the United States market in 2000, and from the Japanese market soon afterwards. It did not get approval in the rest of Europe.

Contents

1Mechanism of action

2History

3Mechanisms of hepatotoxicity

4Lawsuits

5References

6External links

Mechanism of action

Troglitazone, like the other thiazolidinediones (pioglitazone and rosiglitazone), works by activating peroxisome proliferator-activated receptors (PPARs).

Troglitazone is a ligand to both PPARα and – more strongly – PPARγ. Troglitazone also contains an α-tocopheroyl moiety, potentially giving it vitamin E-like activity in addition to its PPAR activation. It has been shown to reduce inflammation:[4] troglitazone use was associated with a decrease of nuclear factor kappa-B (NF-κB) and a concomitant increase in its inhibitor (IκB). NFκB is an important cellular transcription regulator for the immune response.

History

Troglitazone was developed as the first anti-diabetic drug having a mechanism of action involving the enhancement of insulin sensitivity. At the time it was widely believed that such drugs, by addressing the primary metabolic defect associated with Type 2 diabetes, would have numerous benefits including avoiding the risk of hypoglycemia associated with insulin and earlier oral antidiabetic drugs. It was further believed that reducing insulin resistance would potentially reduce the very high rate of cardiovascular disease that is associated with diabetes.[5][6]

Parke-Davis/Warner Lambert submitted the diabetes drug Rezulin for U.S. Food and Drug Administration (F.D.A.) review on July 31, 1996. The medical officer assigned to the review, Dr. John L. Gueriguian, cited Rezulin's potential to harm the liver and the heart and he questioned its viability in lowering blood sugar for patients with adult-onset diabetes, recommending against the drug's approval. After complaints from the drugmaker, Gueriguian was removed on November 4, 1996 and his review was purged by the F.D.A.[7][8] Gueriguian and the company had a single meeting, at which Gueriguian used "intemperate" language; the company said its objections were based on inappropriate remarks made by Gueriguian.[9] Parke-Davis said at the advisory committee that the risk of liver toxicity was comparable to placebo and that additional data of other studies confirmed this.[10] According to Peter Gøtzsche, when the company provided these additional data one week after approval, they showed a substantially greater risk for liver toxicity.[11]

The F.D.A. approved the drug on January 29, 1997, and it appeared in pharmacies in late March. At the time Dr. Solomon Sobel, a director at the F.D.A., overseeing diabetes drugs, said in a New York Times interview that adverse effects of troglitazone appeared to be rare and relatively mild.[12]

Glaxo Wellcome P.L.C. received approval from the British Medicines Control Agency (MCA) to market troglitazone, as Romozin, in July 1997.[13] After reports of sudden liver failure in patients receiving the drug, the Parke-Davis and the FDA added warnings to the drug label requiring monthly monitoring of liver enzyme levels.[14] Glaxo removed troglitazone from the market in Britain on December 1, 1997.[7] Glaxo had licensed the drug from Sankyo Company of Japan and had sold it in Britain from October 1, 1997.[15][16]

On May 17, 1998, a 55-year-old patient named Audrey LaRue Jones died of acute liver failure after taking troglitazone. Importantly, she had been monitored closely by physicians at the National Institutes of Health as a participant in the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) diabetes prevention study.[17][18] This called into question the efficacy of the monitoring strategy. The N.I.H. responded on June 4 by dropping troglitazone from the study.[8][19] Dr. David J. Graham, an F.D.A. epidemiologist charged with evaluating the drug, warned on March 26, 1999 of the dangers of using it and concluded that patient monitoring was not effective in protecting against liver failure. He estimated that the drug could be linked to over 430 liver failures and that patients incurred 1,200 times greater risk of liver failure when taking Rezulin.[8][20] Dr. Janet B. McGill, an endocrinologist who had assisted in the Warner–Lambert's early clinical testing of Rezulin, wrote in a March 1, 2000 letter to Sen. Edward M. Kennedy (D-Mass.): "I believe that the company . . . deliberately omitted reports of liver toxicity and misrepresented serious adverse events experienced by patients in their clinical studies."[21]

On March 21, 2000, the F.D.A. withdrew the drug from the market.[22] Dr. Robert I. Misbin, an F.D.A. medical officer, wrote in a July 3, 2000 letter to the House Energy and Commerce Committee of strong evidence that Rezulin could not be used safely, after having been threatened by the FDA with dismissal in March 2000.[7][23] By that time the drug had been linked to 63 liver-failure deaths and had generated sales of more than $2.1 billion for Warner-Lambert.[20] The drug cost $1,400 a year per patient in 1998.[16] Pfizer, which had acquired Warner-Lambert in February 2000, reported the withdrawal of Rezulin cost $136 million.[24]

Mechanisms of hepatotoxicity

Since the withdrawal in 2000, mechanisms of troglitazone hepatotoxicity have been extensively studied using a variety of in vivo,[25] in vitro[26] and computational methods.[27] These studies have suggested that hepatotoxicity of troglitazone results from a combination of nonmetabolic and metabolic factors.[28] The nonmetabolic toxicity is a complex function of drug-protein interactions in the liver and biliary system. Initially the metabolic toxicity was largely associated with reactive metabolite formation from the thiazolidinedione and chromane rings of troglitazone. Moreover, the formation of quinone and o-quinone methide reactive metabolites were proposed to be formed by metabolic oxidation of the OH group of the chromane ring.[25] Detailed quantum chemical analysis of the metabolic pathways for troglitazone has shown that quinone reactive metabolite is generated by oxidation of the OH group, but o-quinone methide reactive metabolite is formed by the oxidation of the methyl (CH3) groups ortho to the OH group of the chromane ring.[27] This understanding has been recently used in the design of novel troglitazone derivatives with antiproliferative activity in breast cancer cell lines.[29]

Lawsuits

In 2009 Pfizer Inc. resolved all but three of 35,000 claims over its withdrawn diabetes drug Rezulin for a total of about $750 million. Pfizer, which acquired rival Wyeth for almost $64 billion, paid about $500 million to settle Rezulin cases consolidated in federal court in New York, according to court filings. The company also paid as much as $250 million to resolve state-court suits. In 2004, it set aside $955 million to end Rezulin cases.[30]

^ abFisher, Lawrence (17 January 1998). "Drug Makers at Threshold of a New Therapy; With a Dose of Biotechnology, Big Change Is Ahead in the Treatment of Diabetes". The New York Times. Retrieved 12 December 2012.

^Diabetes Prevention Research Group (April 1999). "Design and methods for a clinical trial in the prevention of type 2 diabetes". Diabetes Care. 22 (4): 623–634. doi:10.2337/diacare.22.4.623. Retrieved 12 December 2012.

^Diabetes Prevention Program Research Group (7 February 2002). "Reduction in the Incidence of Type 2 Diabetes with Lifestyle Intervention or Metformin". The New England Journal of Medicine. 346 (6): 393–403. doi:10.1056/NEJMoa012512. PMC 1370926 . PMID 11832527. Retrieved 12 December 2012.

Adipocytes play a vital role in glucose metabolism. 3T3 L1 pre adipocytes after differentiation to adipocytes serve as excellent in vitro models and are useful tools in understanding the glucose metabolism. The traditional approaches adopted in pre adipocyte differentiation are lengthy exercises inv

BACKGROUND: Acne is a chronic inflammatory disease in sebaceous glands and pilosebaceous units where excess sebum production and follicular hyperkeratinization are observed. Adapalene, which exerts comedolytic and anti-inflammatory effects, is used for the topical treatment of mild to moderate acne.

関連リンク

Troglitazone (Rezulin, Resulin, Romozin, Noscal) is an antidiabetic and anti- inflammatory drug, and a member of the drug class of the thiazolidinediones. It was prescribed for patients with diabetes mellitus type 2. It was developed by Daiichi ...